Implement the Text Tool and text layer MVP (#492)

* Add text tool

* Double click with the select tool to edit text

* Fix (I think?) transitioning to select tool

* Commit and abort text editing

* Transition to a contenteditable div and autosize

* Fix right click blocking

* Cleanup hints

* Ctrl + enter leaves text edit mode

* Render indervidual bounding boxes for text

* Re-format space indents

* Reflect font size in the textarea

* Fix change tool behaviour

* Remove starting text

* Populate the cache (caused doc load bug)

* Remove console log

* Chrome display the flashing text entry cursor

* Update overlay on input

* Cleanup input.ts

* Fix bounding boxes

* Apply review feedback

* Remove manual test

* Remove svg from gitignore

Co-authored-by: Keavon Chambers <keavon@keavon.com>

graphene/src/layers/layer_info.rs

@@ -2,6 +2,7 @@ use super::blend_mode::BlendMode;
 use super::folder::Folder;
 use super::simple_shape::Shape;
 use super::style::ViewMode;
+use super::text::Text;
 use crate::intersection::Quad;
 use crate::DocumentError;
 use crate::LayerId;
@@ -14,6 +15,7 @@ use std::fmt::Write;
 pub enum LayerDataType {
 	Folder(Folder),
 	Shape(Shape),
+	Text(Text),
 }
 
 impl LayerDataType {
@@ -21,6 +23,7 @@ impl LayerDataType {
 		match self {
 			LayerDataType::Shape(s) => s,
 			LayerDataType::Folder(f) => f,
+			LayerDataType::Text(t) => t,
 		}
 	}
 
@@ -28,6 +31,7 @@ impl LayerDataType {
 		match self {
 			LayerDataType::Shape(s) => s,
 			LayerDataType::Folder(f) => f,
+			LayerDataType::Text(t) => t,
 		}
 	}
 }
@@ -158,6 +162,20 @@ impl Layer {
 			_ => Err(DocumentError::NotAFolder),
 		}
 	}
+
+	pub fn as_text_mut(&mut self) -> Result<&mut Text, DocumentError> {
+		match &mut self.data {
+			LayerDataType::Text(t) => Ok(t),
+			_ => Err(DocumentError::NotText),
+		}
+	}
+
+	pub fn as_text(&self) -> Result<&Text, DocumentError> {
+		match &self.data {
+			LayerDataType::Text(t) => Ok(t),
+			_ => Err(DocumentError::NotText),
+		}
+	}
 }
 
 impl Clone for Layer {